Hello Yogesh! There’s no limit to the number of Viewers or Viewer-Restricted users you can add to your Figma prototype file—you can invite as many people as needed.
That said, for the best performance, we recommend keeping simultaneous viewers under 500. 

For more information, you can have a look at our Help Center article: How many people can be in a file at once? 

I hope this clarifies!

Hello Team, Could you please inform me about the maximum number of users that can be added to a Figma prototype file with view access? for org level having more than 1000 employees

Hi ​@cmsr, 

You can invite up to 500 collaborators to a Figma prototype file.
You can learn more about collaboration file limits here: https://help.figma.com/hc/en-us/articles/1500006775761-How-many-people-can-be-in-a-file-at-once